Instrument for grinding and polishing diamonds



Aug. 28,1945. J -RQSNER 4 Y 2,383,619

- INSTRUMENT FOR GRINDING AND POLISHING DIAMO-NDS 'Filed Nov. 24,1945 2 Sheets-Sheet 1 v -INVENTOR'. Jada ifasvwr JTTOR/VE) Aug-+28, 1945. J. ROSN-ER INSTRUMENT FOR GRINDING AND POLISHING DIAMONDS I Filed NOV. 24, 1943 2 Sheets-Sheet 2 I INVENTOR.

fut/a RUSH/1 BY p (i 7/:"(Kwfu Patented Aug. 28, 1945 o MIR 1). STAT ES ATENT' ZI OF E-ICE I INSTRUMENT FOR GRINDING A D 1 POLISHING DIAMONDS 'JudaRosner, Brooklyn, "f-A plicatio Noyembei- 24,- 1943,. Serial No. 511 ,612 I.

I v 1 Claim. (01.514229) I My invention relates to improvements in devices for holding diamonds and other precious stones while theyare ground and polished, and particularly-to anew anduseful instrument adapted to .be held by the operator-above a rotating grinding table at any desired and required angle in order to subject .the stone to, various polishing and grinding operations by raising and-lowering .thein'strumentat any desired angle against the rotating table.

According to my invention, the diamond or other precious stone is held in a cup by means of a special'incandescent or heat-proof paste, baked therein and held during this operation in the cup by means of a special finger having a blunt end engaging the stone during the setting of the paste.

The instrument is provided with a plurality of indicators or dials as for instance a means for indicating the position of the stone relatively to the. face of the polishing disc as the grain of the stone requires, automatically, thus doing away with the necessity of frequent trials.

It will therefore with the instrument according to my invention not be necessary to remove the stone from the instrument until all operations are finished all around.

Another indicator on the holder according to my invention discloses the number of rotations of the stone necessary to bring it into its proper position by an audible click produced by the engagement of a spring controlled pin in suitable holes in any required number arranged in the stone carrying spindle.

Still another indicator or scale on the tool indicates the angular position of the tool during the successive grinding ofthe various facets.

The instrument can also conveniently be used in polishing the flat upper face of the stone and and the adjoining angular, upper portions of the facets.

It is furthermore an object of my invention to provide the instrument with a suitable handle, one end of which is mounted on a carriage provided with means for raising and lowering this end of the handle until the same is entirely level as indicated by a suitably arranged level or gage whereupon the same is locked in its adjusted position.

It is the main object of my invention to provide an instrument of this character which works perfectly automatically and with precision during the various steps of polishing and-grinding stones so as to save time and labor lost by the necessity of making various tentative adjustments.

during setting of the paste.

These and other objects and advantages of. my invention will become more fully known as the description thereofproceeds, and will then 'be specifically defined in the appended claim.

Intheaccompanying drawings forming amaterial, part of this disclosure:

Fig. 1 is a topplan view of an'instrument con structed according tomyinvention. I

'FigLZ is-a side elevation thereof.

' Fig. 3 is a section on lined- 3 of Fig. '2.

Fig. 4*is asectionalelevation of the diamond holder, the section being take'nron 'line '44 of Fig. 1.

Fig. 5 is a section on line 5--5 of Fig. 4.

Fig. 6 is a bottom plan View of the lower part of Fig. 4.

Fig. .7 is a section on line 1-1 of Fig. 4.

Fig. 8 is a detail View illustrating the notch of the finger in engagement with a facet.

Fig. 9 is a side elevation showing the instru ment in'an inclined position to the table.

As illustrated, the diamond I0 is pasted and held in a cup II, securely held by means of a set screw l2 in the open end of a substantially vertical spindle l3 or the like having a reduced upper end M carrying a knurled knob l5. The spindle l3 has in its circumference within the block l6, preferably eight holes I1 into which engages successively and laterally a pin 18 controlled by a spring 19, so that when the spindle I3 is turned, by the knob 15, an audible click is heard. The block it carries a scale Or dial 20 corresponding with its graduations to the. eight holes I! in spindle l3. A finger 2! has a blunt end 22 engaging therewith and holding the stone in its cup I I intermediate slot 23 in which is displaceably arranged a screw 24; By looseningthe screw 24, the finger 2| can be turned so as to allowthe use of both of its ends. means of this adjustable screw-24 at the lower end of a holder'25, which can be raised or lowered by the knurled knob 26 at the'outer end of a screw spindle 2! about which a spring 28 is wound within a chamber 29 in the holder 25. In order to adjust the diamond or stone on the instrument at an angle to the grinding table 30, an adjusting screw 3| is provided which can be operated by means of a knurled knob 32 .and which can be turned in any of its adjusted. angles against the table, indicated on dial 33, if a nut 35 is loosened to allow an adjustment about the axis of shaft l3 when the same is loosened which normally locks an element 56 of the instrument against movement relatively to block l6. The

This finger has an i The finger 2| is held by' finger 2| has at its end opposite to the blunt end 22, a notch 36 to engage the facet edges at the lower end of the stone, as illustrated in Fig. 8.

The handle 31 of the instrument has its shaft 38 secured by means of a cap nut 39 to the upper end of a screw 40 having two flattened side faces andcarrying a boss 4| in which a rod 42 is held. The screw 4|] passes through a carriage 43 on wheels 44, 45 and can be adjusted in vertical direction by thexproper operation of an adjusting nut 46 to be locked in its adjusted position by means of the nut 41.

Stop pins 48 and 49 on'the work bench serve I as shown at 54, in order to indicate tests of the v position of the stone withrespect to the grain of the stone to be worked upon. The nut is locked in-its adjusted position by means of the cap nut 55 on spindle 52. I

In operation, if grindin of the flat face of the stone and of the angular faces adjoining the fiat face, is desired, the finger 2| is removed, and the stone is pressed by means of the instrument handle against the grinding table. First test by tuming the dial nut 53 is made to turn the instrument without disturbing its prior adjustments in order to ascertain whether the stone is presented to the face of the polishing disc as the grain of the stone requires. Then the proper adjustments of the angles in which the instrument is to be held against the table are made in order to properly grind the facets.

It will be understood that I have described and shown the preferred form of my instrument only as one example of the many possible ways to practically construct the same, and that I may make such changes in the general arrangement and in the construction of the minor details of the invention as come within the scope of the appended claims without departure from the spirit of my invention and the principles involved.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent is:

In an instrument for grinding and polishih diamonds, a carriage, a block mounted on one end of said carriage, a holder having a cupshaped end for retaining a cemented diamond mounted on said block, a fingerfor holding the diamond in said cup during drying of the cement and during grinding, said finger having a blunt end to hold the diamond during the drying operation and a notched end for engagement with the facets of the diamond during the grinding operation and said finger also having a longitudinally slotted central portion between the blunt and notched ends, a screw threaded into said block and extending through the slotted' portion of said finger whereby said finger is adjustable'to engage the diamond with either the blunt or notched end.

JUDA ROSNER. 

